Synchrotron X-ray powder diffraction studies of solubility limits in the LiFe5O8-LiAl5O8spinel solid solutions

Abstract

The formation of substitutional solid solutions between the isostructural LiFe5O8 and LiAl5O8 was studied by synchrotron X-ray powder diffraction from room temperature up to 900°C. Structural characterization and distribution of cations in the A and B spinel sublat- tices for LiFe2.5Al2.5O8 were obtained by Rietveld structure refinement. We report new re- sults on the solubility limits in the LiFe5O8-LiAl5O8 system. The "iron-rich" (LiAl1.2Fe3.8O8) and "aluminum-rich" (LiFe1.2Al3.8O8) solid solutions coexisted during the thermal treatment up to 900°C, and the formation of single-phase spinel solid solution was not observed.